There have been many methods for the surface mounting of radio frequency components, in particular those components which interact with signals having frequencies between approximately one kilohertz and approximately twenty six gigahertz. An example of such a prior art surface mounting method for radio frequency components required the use of a circuit board having a number of traces thereon in cooperation with components having electronic devices on a carrier. A pair of input/output launch pads, or contact areas, located on the underside surface of the carrier member connected to the electronic devices provide an external connection point to the component.
The prior known method requires the components to be positioned on the circuit board according to a predetermined design. Once positioned, the contact points of the components have been connected to the traces by soldering. The components have been oriented on the circuit board to position the edges of the components preferably at right angles to the traces to avoid unwanted perisitic effects where at least a portion of the high frequency signal can otherwise be lost.
While the prior known surface mounting technique for radio frequency components has served its purpose generally in facilitating the assembly procedure, it has not provided a designer of radio frequency circuits with much flexibility. The lack of flexibility relates to the requirement for customization in the development process. The design of radio frequency circuits is an application specific undertaking. The designer must not only specify the types of electronic devices contained within the component, but also specify the configuration of the board layout for the components for each radio frequency application. The configuration of each one of the components is important, since it is desirable to have a high density clustering of the components on the board to reduce its overall size. As a result, the designer must not only design the layout of the traces on the circuit board, but also design the configuration of the components to be used with the custom designed circuit board.
Efficiency can be increased by the designer by creatively arranging the positions of the components in the layout of the board. However, the customization of each one of the components and the board layout required greatly increases the cost of producing radio frequency devices.
Therefore, it would also be highly desirable to have a new and improved method of surface mounting radio frequency components which does not require, or at least greatly reduces, required customization of the radio frequency components and the associated board layout, and which permits the manufacturing of radio frequency devices in a relatively inexpensive manner.
Another drawback of the conventional surface mounting technique for radio frequency components relates to the layout of the traces used to connect components. Due to the inherent characteristics of radio frequency signals, the traces are positioned on the circuit board in such a manner to eliminate right angle bends therein. Thus, instead of using a simple right angle bend to redirect the course of a trace, designers have resorted to the use of mitered corners and interconnecting trace segments at less severe angles, to achieve a desired circuit within the constraints imposed by the size of the circuit board.
Using mitered bends and other such design restrictions for the traces, the amount of circuit board is undesirably large to accommodate all of the required traces. The result has been an overly large board with a less than desirable density of components.
This inefficient use of the circuit board is even more apparent when bends and turns to the trace are required. For example, a 180.degree. "U"-turn in a trace connecting two parallel chains of radio frequency components, such as filters, requires the dedication of a large area of the circuit board to accommodate a segmented U-shaped trace. Thus, valuable space on the board to accommodate the large U-shaped segmented trace is lost. Also, the U-shaped trace can cause an unwanted and undesirable loss of the radio frequency signal.
Therefore, it would also be highly desirable to have a new and improved method of surface mounting radio frequency components in a more effective manner.